Mixer-based, vector-corrected, vector signal/network analyzer offering 300kHz-20GHz bandwidth and traceable phase response

We describe an instrument that uses directional bridges and a five-channel, mixer-based receiver to make vector-corrected measurements of signals from 0.3MHz to 20GHz. This instrument yields voltage, current or travelling waves in either time-domain or frequency-domain with /spl ap/85dB SFDR and with phase accuracy that can be traced to national standards laboratories. The instrument is used to characterize the effect of an amplifier on a wideband complex-modulated signal. Results are compared with data gathered using a calibrated sampling oscilloscope equipped to capture long records with timebase correction. We show effects such as input-impedance induced distortion that can be seen only with this new instrument.